Controlled stroke, piston type gas generator for producing gas to operate turbines, etc.



Nov. 13, 1956 v. E. PALUMBO 2,770,225

CONTROLLED STROKE, PISTON TYPE GAS GENERATOR FOR PRODUCING GAS TO OPERATE TURBINES, ETC

4 Sheets-Sheet 1 Filed Sept. 17, 1954 l/l/vceur ipaz/naa Armmsy 2,770,225 TOR FOR V. E. PALUMBO Nov. 13, 1956 CONTROLLED STROKE, PISTON TYPE GAS GENERA PRODUCING GAS TO OPERATE TURBINES, ETC

4 Sheets-Sheet 2 Filed Sept. 17, 1954 11v VEN'TOR. Vmcsur. Era/Mao Armemsy NW aw NV NEIQ l k Nov. 13, 1956 v. E. PALUMBO CONTROLLED STROKE, PISTON TYPE GAS GENERATOR FOR PRODUCING GAS TO OPERATE TURBINES, ETC

4 Sheets-Sheet 3 Filed Sept. 1'7, 1954 m INVENTOR. V/NcE/YrTPALz/Mw xx mm Nov. 13, 1956 v. E. PALUMBO CONTROLLED STROKE, PISTON TYPE GAS GENERATOR FOR PRODUCING GAS TO OPERATE TURBINES, ETC

4 Sheets-Sheet 4 Filed Sept. 1'7, 1954 I N V EN TOR.

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United States Patent 9 CONTROLLED STROKE, PISTON TYPE GAS GEN- ERATOR FOR PRODUCING GAS TO OPERATE TURBINES, ETC.

Vincent E. Palumho, Cleveland Heights, Ohio Application September 17, 1954, Serial No. 456,795

9 Claims. (Cl. 1 2358) This invention relates to improvements in the class of piston type gas generators that are used for producing high temperature and/or pressure fluid for driving turbines, FOI operating other pressure fluid apparatus.

The gas generator of my invention is distinguished from the type of apparatus, commonly known as free piston engines, that are employed for the same purpose, by the inclusion of cam actions that synchronize the operation of the pistons and, in so doing, confine the pistons to a definite unchanging length of stroke.

One object of the invention is to produce a gas generator in the generator.

ICE

in a plane parallel to that of Fig. l, the piston structures, engine shaft, and the cams through which said structures are operatively connected to the shaft, being shown in elevation;

Fig. 4 is a transverse section through the generator on the lines 4-4 of Figs. land 3 Fig. 5 is a similar sectional view taken on the lines 5-5 01 Figs. 1 and 3 and Figs. 6 and 7 are an elevational view and a sectional View, respectively, of a check valve of the type employed The generator housing as a whole is designated by the reference numeral 1. It is composed of a central housing sect on 2, compressor or pump housing sections 3 and 4 thatare connected to the ends of the section 2. in a rnanner hereinafter to appear, and individual cylinder blocks of the aforesaid class that is highly efiicient in that a relatively low percentage of the energy derived from the fuel is absorbed in friction, wherefore the energy in the high temperature and/or fluid pressure that is delivered by the gas generator is relatively high.

Another object of the invention is to provide a prime mover of the class aforesaid that can be readily started by rotating the cams that control the movement of the pistons, this being among the advantages in the use of the aforesaid cam actions. This simple starting arrangement eliminates the need for using high pressure starting :air on the compressor pistons which is the conventional mode of starting the free piston type of engines. Further advantages accruing from the same source are the provisions for operating customary adjuncts ofapparatus of the kind to which the invention pertains, such as .oil pumps; water pumps, and fuel pumps, to name a few.

in other words it is an object of the invention toprovide a piston type gas generator which has as itsgmain purpose the: generation and delivery of high energy and which is highly efficient inthis respect, and yet of a sufficiently conventional nature as to make available for use therewith engine appurtenances that are standard iandproven. A further object of the invention is to provide a sturdy, simple and relatively compact structure 7 embodiment of the invention illustrated inthe accom- J panying drawings wherein like parts are designated by. like F reference numerals throughout the several views.

lnthe drawings, p F s ,Fig. l is an elevational view of myimprovedpiston type gas generator;

designated 5, 6, 7 and 8, which, with closure plates, are mounted on the ends of the sections 3 and 4.

The central housing section 2 is made up of two identical halves that are joined together in a manner presently to be described and which, for descriptive purposes, will be considered a single unit. Said unit includes an inner wall 10, end walls 11 and 12, and outer wall sections 13 and 14 that are shown as. formed integral with the end walls and that overhang the ends of the Wall 10. Intermediate the wall sections 13 and 14, and in approximately flanges .18 that are secured together. by bolts 19; and dis posed between and secured to the outer wall sections of each of the housing halves are shells 2t) and ,21, desirably formed from steel plate of appropriate thickness, each shell being substantially semi-elliptical in cross section. Saidshe'lls are fastened to the wall sections by screws 22. The joints between the flanges 12B and. between the adjacent edges of the opposed shells 2i and 21 may be sealed by strips of suitable packing material, or by a caulking compound applied thereto, as will be readily understood by those skilled in the art. The flanges 18 may extend from end to end of'the central housing section, as indicated in dotted lines in Fig; l, and said ,flanges may be 1 Walls 10,111, 13,314 and 16, together with the shells 2s Fig. 2. is another elevational View of the generator as it would appear from below l, with. parts broken away;

Figs. 3 and 3?, when joined by registering the line a -zz of the former view with the line b-b of the latter,repre are the halves of a bearing 38! sent a central longitudinal section through the generator and 2 and, as will presently, appear, "such space con stitutes an air chamber 25.

Each half of the central housing section 2 consists of an integral casting that includes, midway between its ends, a cylinder block 28 that encloses a double lengthpower cylinder 31 that is open at its ends. The peripheralwall of each cylinder 3i) is provided, adjacent one end thereof, with one or more inlet ports 31 through which the cylinder communicates with the air spac ZS, and adjacent the opposite end thereof, with one or more exhaust ports 33 that lead "to an outlet. connection 34.. A fuel injector 35 is supported within a tubular boss 36 that extends from the cylinder wall tothe wall section 16, and said injector has its discharge end. directed into the cylinder rriidway 7 between the ports 31 and 33. The Walls of the cylinder block, and those constituting the outlet connections 34.

and-the bosses 36 are shown as cored orchamberedfor the circulation of a coolant, such as water, in accordance with common practice. lndicatedas formed integral with the cylinder blocks 23, midway between'the ends thereof,

' In view of the fact that the overall structure is identical above and-below its longitudinal axis (as thesame is are used to designate the corresponding parts above and below said axis.

The outer wall sections 13 and 14 of the central housing unit 2 are provided with inlet connections 40, shown as flanged at their outer ends for the purpose of joining them in a well known manner to intake manifolds (not shown), should such an arrangement be desired. Under some circumstances said inlet connections may communicate directly with the surrounding atmosphere. Associat'ed with these inlet connections are partitions 42 that are desirably cast integral with the central housing section, and said partitions set off inlet ducts 43 that lead to ports 44 in the end walls 11 and 12. As will be evident from Fig. 4, each partition 42 joins the adjacent end wall in about the central-plane of the structure. The ports 44 are thus placed in communication with the corresponding inlet connections 40, and are separated from adjacent ports 45 in said end wall. The purpose of the latter ports will presently appear.

Controlling the flow of air through the ports 44 are check valves generally denoted 46, and controlling the passage of pressure fluid through the ports 45 are similar check valves 47. A valve of this character is disclosed in my copending application Serial No. 394,639, filed November 27, 1953, and is shown herein in detail in Figs. 6 and 7.

Each of the previously mentioned housing sections 3 and 4 desirably consists of an integral unit or casting that encloses two pump or compressor cylinders 50, each such section or unit having a central axial opening 51 within one end of which is contained a bearing 52 that is flanged at one end and held in place by an element 53. The opposite end of the opening 51 is closed by a sealing ring 54 of a common sort. The inner ends of the housing sections 3 and 4 are engaged with depressed seats in the end Walls 11 and 12, and applied to the outer ends of said sections 3 and 4 are circular closure plates 56 provided with central openings 57, said plates having annu-v 1ardepressed seats for engagement with the ends of the sections 3 and 4 about the cylinders 50. It is directly to these closure plates 56 that the individual cylinder blocks 5, 6, 7 and 8 are applied. The inner end of each of these cylinder blocks is provided with a flange 58, and through registering holes in said flange and in the underlying plate 56, and through aligned longitudinal bores of the housing sections 3 and 4, are engaged long bolts 61) that have their threaded ends screwed into tapped holes'in the end walls 11 and 12, thereby to secure the several constituents of the housing together.

Each of the cylinder blocks 5, 6, 7 ands desirably consists of an integral casting and includes an inner wall 62 and an outer wall 63, between which is an air space or compartment 64. The inner wall 62 constitutes the peripheral wall of a power cylinder 65, and through one or more inlet ports 66 therein, aid cylinder communicateswith the air space or compartment 64. Opening through the wall 62 into the power cylinder, substantially opposite the ports 66, are exhaust ports 68 that lead to a flanged outlet connection 69, similar to those previously mentioned and designated 34. The inner end of the power c'ylinder registers with the opening 57 of the corresponding closure plate 56, while the opposite end of the cylinder is closed by a head 70, held in place by fastening means 71, shown as studs and nuts, and the head is provided with a centrally located hollow boss 72, within which is disposed a fuel, injector 74 that has its discharge end projecting into the cylinder. The head 70, the wall 62, and the wall that surrounds and defines the outlet connection 69, are chambered or cored to provide circulating spaces for a suitable, liquid coolant. It will be observed that the walls of the housing sections 3 and 4 that surround the compression or pump cylinders 50 are similarly treated for the circulation of a coolant. means of cooling the various cylinders is common in this class of apparatus, and it will be understood that provisions are made for conducting a liquid coolant to and from the coolant'spaces, in accordance with common practice. Although not illustrated herein, it will be further understood that a pump may be included in the coolant circulating system and, as hereinbefore related, such pump may be driven by the shaft of the apparatus or gas generator.

It will be seen that the structure thus far described provides four groups of cylinders, two such groups at each end of the structure, and operatively associated with each of the groups adjacent the left hand end of the apparatus, as viewed in Fig. 3 are piston structures designated generally by the reference numeral 75, and similarly' associated with the groups at the right hand end of the apparatus, as shown in Fig. 3 are piston structures 76.

Each piston structure 75 or 76 terminates at its inner end in a piston 89 that operates in the adjacent end of one of the double power cylinders 30, and, at its outer end, in a piston 81 that operates in the corresponding power cylinder 65. Each of the piston structures also includes a pump or compressor piston 34 that is between, and of a diameter considerably greater than that of, the pistons and 81, and it is reciprocable in the corresponding cylinder 50.

It will be seen by reference to Figs. 2 to 4 in particular, that each of the compressor or pump cylinder 50 communicates, at one end, with the air space or compartment 25, through the ports 45 that are controlled by the check valves 47, and with the inlet ducts 43, through the ports 44 that are controlled by the check valves 46. The opposite end of each of the cylinders 50 has communication with the air space or compartment 64 of the adjacent cylinder block 63 through a port 86 that is controlled by a check valve 87. Now, by reference especially to Figs. 3 and 5, and remembering that all of the cylinder blocks 5, 6, 7 or 8 are identical, it will be comprehended with respect to each, that an air passage 90 is set 01f from the air space or chamber 64 by a partition 91. The air passage 90 communicates with the atmosphere through an inlet connection 93, similar to the previously described air inlet connections designated 40. Said inlet connection may open directly to the atmosphere, or, in some situations, it may be connected to a manifold that is common to all inlet connections that are in alignment longitudinally of the apparatus, as will be readily understood. The passage 90 of each of the individual cylinder blocks communicates With the adjacent compression or pump cylinder 50 through ports 94, controlled by a check valve A shaft 1% extends lengthwise through the apparatus or generator and is desirably arranged with its axis substantially coincident with that of the housing 1. It is of maximum diameter at its longitudinal center where it is journaled in the beforementioned bearing 38. The shaft is shown as stepped down in diameter from said portion of-maximum diameter toward each end, and the parts of minimum diameter, as herein shown, are journaled in the previously mentioned bearings 52 that are contained in the central openings 51 of the housing sections 3 and 4. Mounted upon the shaft 100, immediately outwardly of the transverse planes of the open ends of the cylinders 30, are cams designated generally by the reference numerals MP4 and 105. Each of these cams comprises, in the present instance, a cylindrical body or hub 106 that is secured against rotation to the shaft as by means of a pin 107, and said body or hub is surrounded by an endless helical rim 110, having opposed cam faces 111. The rim is shown as connected to and spaced radially from the .by reversely inclined reaches that are joined through socalle'd"turns or curved portions which define the end This provide a recess 115. The rim 110 of the adjacent cam 104 or 105 is accommodated by said recess. Each recess at the end thereof adjacent the piston 80 is undercut to leave an arm 116, and occupying the space between the inner side of said arm and the opposed wall of the recess is a cam follower or roller 113. The peripheral face of said roller is desirably axially curved on a radius which has its center coincident with that of the roller. In other words, said face is spherical. A similar roller 119, corresponding to each of the rollers 118, engages the opposite cam face 111 of the rim 110 and is disposed between an arm 120 and the opposed wall of the recess 115. The arm 121) is a part of a cross member 122 that ties the opposed piston structures together and maintains them in absolute parallelism, the ends of the member being connected to the structures by screws 123. It will be observed that there are two cross members 122, each including two arms 12!), and that one of said members connects the opposed piston structures 75 and the other the piston structures 76. As best appears from Fig. 4, the body portion of the member 122 is in the form of a bar that is enlarged midway between its ends and is provided with a central aperture 125 through which the shaft 1100 extends. As will be apparent from the construction, the tie members 122 hold the opposed piston structures to which they are secured against turning, thereby to insure proper relationship at all times between the cam followers of rollers 118, 119, and the grooved faces 111 of the cams. Otherwise binding would occur.

In Fig. 3 one of the rollers 119 is shown in section. Said roller is provided with a bushing 126 that is journaled on a hollow, headed stud 127. The stud is projected through aligned apertures in the arm 120 and in the opposed portion of the piston structure and is held in place by a washer 128 and a screw 129, the latter being threaded into the stud. The screw and washer, like the head of the previously mentioned screws 123, is accommodated by a recess in the piston structure. It will be understood that all rollers 118 and 119 are constructed and supported in the same manner as the one just described. The opposed cam faces 111 of the rim 110 of each of the cams 1194 and 1&5 are shaped for perfect contact at all times with the followers or rollers 118 and 119, regardless of the constantly changing length of line contact between the rollers and the cam faces, due to the successive engagement of the turns and inclined reaches of the cam faces with the rollers. This perfect contact is accomplished, I may explain, by using cutters or tools having cutting edges corresponding in profile with the rollers for cutting said faces, and that are operated in the same relationship to the cam faces as are the rollers herein.

In considering the operation of the apparatus, it will be assumed that the same has been started, as by means of an electric motor (not shown) that has driving connection with the shaft we, and that an explosition has occurred in eachof the cylinders 31?. With the pistons 80 driven by the force of the explosion to the outer ends of their strokes, air will rush into the cylinders 30 through the ports 31 from the air spaces or chambers 25, scavenging the cylinders of the products of combustion that escape through the ports 33 into the outlet connections 34. As shownat the top of Fig. 1, the outlet connections are joined to a manifold 130 which, with a similar manifold attached to the. opposite outlet connections, carries the high temperature, high pressure gases to a place of use or accumulation. v 1 H it is evident from the nature of the piston structures 75 and as that, whenthe pistons 80 are moved as aforesaid, thepistons S1 willycoinpress the air trapped in the powercylinders 65 and,;upon compression of said air, a charge of fuel will be shot into the cylinders by the fuel injectors 7d Upon ignition of the resultant mixture, an explosion will occur that will drive the pistons 81 forwardly resulting, of course, in inward movement of the pistonsStl thereby to compress air previously admitted to the cylinders 30 through the ports 31 as above explained. When the pistons 81 reach the forward end of their strokes and uncover the ports 66 and 68, air will rush in through the former ports from the spaces or compartments 64, and the exhaust gases will escape through the latter ports into the outlet connections 69 to join those in the manifold 130.

With the advancement of the pistons to the outer end of their strokes, as first above described, the pump or compressor pistons 84 are moved to the outer ends of the cylinders 56, drawing in a charge of air to the rear of the pistons through the ports 44, past the check valves 46, simultaneously expelling the air on the other side of the pistons through the ports 86 and past the check valves 2%? into the spaces or compartments 64. During the power stroke of the pistons 81, as above described, the

pump or compressor pistons 84 will move to the inner ends of the cylinders 50, the air in advance of the pistons being forced through the ports 45 past the check valves 47 and into the spaces or compartments 25, air being drawn into the cylinders 50 on the opposite sides of the pistons through the'p orts 94 past the check valves 95.

As the piston structures are thus reciprocated they will,

through the followers or rollers 113 and 119, drive the cams 1M and to rotate the shaft 100.

While I have disclosed herein the present preferred embodiment of the invention, I wish it to be understood that the invention is susceptible to such changes and modifications as are embraced within the scope of the claims appended hereto. For instance, the shapes of the enacting faces of the cams 104 and 1195 and their followers or rollers 118 and 11? need not necessarily be as shown and described. They might, for example, be tapered as disclosed in my copending application Serial No. 394,649, filed November 27, 1953.

Having thus described my invention, what I claim is:

1. In a gas generator of the class described, a housing, a shaft journaled therein, means on the shaft for converting reciprocatory motion into rotary motion, an

elongate piston structure provided intermediate its ends with means for operatively connecting it to the former means, said structure terminating at each end in a power piston, a pump piston of considerably greater diameter than the power pistons intermediate one of the former pistons and the second mentioned means, the housing including power cylinders wherein the power pistons 'operate and a pump cylinder wherein the pump piston reciprocates, the housing being provided with exhaust ports communicating with the powercyiinders and con trolied by the pistons therein, the housing also enclosing air compartments and being provided with ports through which said compartments communicate with the power cylinders and which are likewise controiled by the power pistons, the housing having passages through which the pump cylinders communicate with said compartments and further passages through which air is admitted to the pump cylinders, self-acting check. valves for controlling the flow of air through said passages, and means for delivering fuel to the power cylinders.

2. In a gas generator of the class described, a housing,

a shaft journaled therein, means on the shaft for con vetting reciprocatory motion into rotary motion, elongate. piston structures spaced substantialiy diametrically apart. on opposite sides of the shaft in parallel relation thereto,

said structures being provided with means for operatively connecting them to the former means, a rigid. tie member disposed in. a plane normal to the axis of the shaft the opposed ends of which are secured to .said piston structures, each piston structure terminating at eachcnd in a power piston, a pump piston of considerably greater diameter than thepower pistons en1-- bodied in each of said structures and located intermediate one of the power pistons and the corresponding second mentioned means, the housing including power cylin-- ders wherein the power pistons operate and pump cylinders wherein the pump pistons reciprocate, the housing enclosing air compartments, and passages through which the pump cylinders communicate with said compartments and with an air supply, self-acting check valves for controlling the flow of air through said passages, the housing also including inlet ports for the power cylinders that lead from said air compartments and exhaust ports that communicate with the power cylinders, all of the ports opening into the power cylinders through the peripheral walls thereof and being controlled by the pistons therein, and means for delivering fuel to the power cylinders.

3. In a gas generator of the class described, an elongate housing, a shaft journaled therein and extending longitudinally of the housing, two separate means on the shaft and spaced apart therealong for converting reciprocatory motion into rotary motion, a pair of diametrically opposed substantially parallel elongate piston structures associated with each of said means, further means on said structures that operatively connect them to the corresponding ones of the first mentioned means, rigid tie members, each having its end secured to opposed piston structures of the same pair and formed intermediate its ends for the accommodation of the shaft, each piston structure terminating at its opposite ends in power pistons and incorporating intermediate one of said pistons and the corresponding further means a pump piston of considerably greater diameter than the power pistons, the housing including power cylinders wherein the power pistons operate and pump cylinders wherein the pump pistons reciprocate, the housing enclosing air compartments, and passages through which the pump cylinders communicate with said compartments and with a source of air supply, self-acting check valves controlling the flow of air through said passages, the housing being provided with ports that open into the power cylinders through the peripheral walls thereof and are spaced apart circumferentially of said walls and are controlled by the power pistons, certain of said ports being inlet ports and communicating with said air compartments, and the others of said ports being exhaust ports, and means for supplying fuel to the power cylinder.

4. In a gas generator of the class described, a main housing section, a shaft journaled therein and extending longitudinally of said housing section, said housing section including cylinder walls that define open-end double length power cylinders which are disposed equal distances from and on opposite sides of said shaft with their axes parallel to the shaft, two separate power transmitting means mounted upon and secured to the shaft and spaced apart longitudinally thereof for converting reciprocatory motion into rotary motion, a pair of opposed piston structures associated with each of said means,

each of said structures terminating at its ends in power pistons, a pump piston of considerably greater diameter 7 than the power pistons incorporated in each of said structures and located adjacent the power piston at the outer end of the structure, the piston at the inner end of the structure operating in one end of one of said double length power cylinders, pump housing sections applied to the ends of the main housing section and enclosing pump cylinders in which the pump pistons op,

self-acting check valves controlling the flow of air through said' passages, each of the cylinder blocks enclosing an air compartment that communicates through a passage with the adjacent pump cylinder, a self-acting check valve.

the how of air through the last mentioned passage, op

erative connections between each of the aforesaid power transmitting means and the opposed piston structures associated therewith, and means for delivering fuel to the power cylinders.

5. In a gas generator of the class described, the combination and arrangement of parts set forth in claim 4, and, in addition thereto, two rigid tie members, each having its opposite ends secured to the opposed piston structures of one pair and which is formed intermediate its ends to accommodate the shaft.

6. In a gas generator of the class described, the combination and arrangement of parts set forth in claim 4, wherein each of the pump housing sections is an integral unit enclosing two pump cylinders and having an opening intermediate said cylinders through which said shaft extends.

7. In apparatus of the class described, a housing, a shaft journaled therein, a cam on the shaft having oppositely facing cam surfaces, elongate piston structures spaced substantially diametrically apart on opposite sides of and like distances from the shaft in parallel relation thereto, rollers carried by said structures for engagement with the aforesaid cam surfaces, the cam engaging face of each roller being spherical and the face of the cam wherewith the roller engages having a surface contour complementary to the profile of said face of the roller, the cam being so shaped that the opposed piston structures are maintained in the same relation to each other at all times during reciprocation, and rigid tie means fixedly secured at its ends to the opposed piston structures and for-med intermediate its ends to provide clearance for the shaft, the housing including cylinders and said structures incorporating pistons that operate within said cylinders, said tie means preventing rotation of the piston structures about their own axes.

8. In apparatus of the class described, a housing, a shaft journaled therein, a cam on the shaft having oppositely facing cam surfaces, elongate piston structures spaced substantially diametrically apart on opposite sides of and like distances from the shaft in parallel relation thereto, followers carried by said structures for engagement with the aforesaid camsurfaces, the followers being mounted to rotate on axes substantially radial with respect to the shaft and being characterized by spherical cam engaging faces, and the cam surfaces of the cam being grooved and of a contour complementary to the profile of said spherical faces, the cam being so shaped that the opposed piston structures are maintained in the same relation to each other at all times during reciprocation, and rigid tie means fixedly secured at its ends to the opposed piston structures and formed intermediate its ends to provide clearance for the shaft, the housing including cylinders and said structures incorporating pistons that operate within said cylinders, said tie means preventing rotation of the piston structures about their own axes.

9. In apparatus of the class described, an elongate housing, a shaft journaled therein and extending longitudinally of the housing, cams mounted upon and secured to the shaft and spaced apart therealong, each cam having undulated oppositely facing cam surfaces, a pair of diametrically opposed substantially parallel elongate piston structures associated with each cam, rollers carried by said structures for cooperation with the cmn surfaces, the

rollers having spherical cam engaging faces, and the cam surfaces wherewith said rollers engage being grooved and of a contour complementary-to the profile of said faces of the rollers, rigid tie members, each having its ends fixedly secured to opposed piston structures of the same pair and formed intermediate its ends for the accommodation of the shaft, the piston structures incorporating pistons and the housing being provided with cylinders wherein said pistons operate.

References Cited in the file of this patent UNITED STATES PATENTS 1,127,267 MoElwain Feb. 2, 1915 1,183,777 Soules May 16, 1916 1,379,774 Murphy May 31, 1921 1,379,775 Murphy May 31, 1921 1,445,686 Hul t Feb. 20, 1923 10 Boyce Feb. 14, 1928 Lee Sept. 6, 1932 Herrrnann May 27, 1941 Mercier June 6, 1950 Sherman Aug. 21, 1951 Palumbo Sept. 11, 1951 FOREIGN PATENTS Great Britain Nov. 11, 1909 France Feb. 26, 1923 Italy July 1, 1930 

